Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare this is a non-readonly, non-idempotent, non-destructive, closed-world write. The description adds behavior annotations cannot express: the first call is a no-op discovery step and the actual method choice belongs to the USER, which is exactly the kind of non-obvious trait an agent needs. It stops short of explaining what each method actually does (e.g. whether `agent` returns an upload target).

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short paragraphs, front-loaded with the purpose and then the call sequence in order; every sentence carries the protocol. Slightly awkward line breaks and the parenthetical format list are the only mild inefficiencies.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The tool is a simple 3-param, zero-required handshake with an output schema (so return shape need not be described) and annotations covering the safety profile. Given that support, the description supplies everything an agent needs to call it correctly: what it does, the two-phase invocation, and that the choice is the user's.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so all three parameters are already documented inline, including the enum values and the 'omit to get both options' default. The description reiterates the `method` handshake but adds nothing about `filename` or `workflow_id` (e.g. the browser-required workflow link) beyond the schema, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a concrete verb+resource ('Get an audio file into Onepin'), names the accepted formats, and ties the result to a 'source_audio node', so the agent knows the artifact and its downstream consumer. It does not explicitly distinguish this from the adjacent `finish_audio_upload` / `upload_script_file` siblings, which keeps it short of a 5.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives an explicit call protocol: invoke with no `method` first (uploads nothing, returns the two options), then re-invoke with the user's choice. That is clear when-to-use guidance and prevents a premature upload. It offers no exclusions or named alternatives among the many sibling upload/list tools, so it stops at 4.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.